<!DOCTYPE html>
<html>
    <head>
        <meta charset="utf-8">
        <title>JavaScript特殊值NaN</title>
    </head>
    <body>
        <h3>JavaScript特殊值NaN</h3>
        <hr />
        <script>
            var x1 = "hello";
			var x2 = 999;
			var result1 = Number(x1);
            alert('x1(hello)是数字：'+isNaN(x1)+'\nx2(999)是数字：'+isNaN(x2)+'\nx1转换为数字的结果为：'+result1);
        </script>
    </body>
</html>